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Now the problem of development of the high-speed and high-speed movement on the main railway transport that is connected by increase of traffic safety of trains and ensuring reliable work of contact suspension brackets and current collectors of an electrorolling stock is actual. For increase of reliable work of current collectors there are some ways one of which is creation of the safety devices which are built in a design of current collectors and providing their automatic lowering in emergencies. In Omsk State Transport University the current collector equipped with safety devices of new generation on the basis of the operated pneumatic devices and providing protection at failure or the increased wear of contact elements, and also breakages of a runner is developed; at rise on height of more admissible at departure of an electrorolling stock for the sign «End of a Contact Suspension Bracket» or break of contact wires; at blows and arrivals on obstacles in a contact suspension bracket. For control and management of operation of safety devices the protective pneumatic contour located on the basis of a current collector in the special case is used. At operation of one of safety devices there is a depressurization of the pneumohighway of a protective contour therefore pressure of compressed air the drive of a current collector decreases and it falls under the influence of own gravity. Restoration of a current collector possibly only in the conditions of depot or point of maintenance of locomotives. Calculation of characteristics and parameters of the device of protection at blows and arrivals on obstacles in a contact suspension bracket needs to be carried out by the given technique for zones of normal, dangerous and emergency work. For an assessment of operability of safety devices and definition of their main technical indicators and parameters in laboratory of OSTU the shock and oscillatory complex is developed for research of interaction of a current collector with a contact network.

The article presents the results of experimental researches of process of commutation in traction DC motors. In order to generalize the results of tests of low power engines for electric locomotive’s traction motors, belonging to high power engines, by using the theory of similarity and dimensions we defined the ranges of varying parameters of the operation mode in the experiments. In result of the conducted researches proved the effectiveness of the parameters of laws of distribution of intensity sparking to improve the reliability of the test as low power engines and high power engines.

The subject of the study is the fuel utilization system of a diesel power plant as a diesel locomo-tive or other vehicle main lead, which is a complex technical system consisting of actual diesel in-ternal combustion engine, fuel lines and low pressure fuel processing and high pressure line includ-ing various elements of liquid fuels consumption dosing and control. The aim of our study was to analyze the system functioning, to determine the dynamic proper-ties and the nature of changes in the internal parameters of the system as a whole. To achieve the goal the system analysis methods were used. The processes of complex technical system operation were interpreted by means of the continuous linear stationary deterministic model of the list of others. For this particular model the body of mathematics developed on the basis of linear differential equations with constant coefficients is the most complete one. The chosen mathematical model was presented by us in the first stage in the form of a finite graph as a subgraph of obtained earlier generalized model which had both methodological and theoretical foundation. In accordance with the methodology of the systematic approach the graph model of the diesel power plant fuel utilization system operation was described in relation to major significant factors affecting the system parameters transformation dynamics. Given the complexity of the of fuel ignition and combustion mechanism located in the diesel engine cylinder, the use of the techniques of the modern automated control theory is adopted for numerical processes simulation with the system described in terms of the said theory. The criteria of efficiency, mechanical loads and thermal loads levels were chosen as the fuel utilization system internal state variables. Taking into account the Pareto principle the most important efficiency criterion components were chosen for the analysis; and the system of differential equations of the efficiency dynamics in the form of three balance equations was created. The factual description of the included equations allowed us to derive preliminary qualitative conclusions about the dynamic properties of the internal criteria: controllability, observability and stability of the fuel utilization system. The differential equations system parameters linearizing procedure and the introduction of small deviations allowed us to obtain the dynamic mathematical model of the fuel and air transfor-mation in the diesel engine heat cylinder. As the result of transformations we have obtained the equations presented in the form of the matrices, which allowed us to conclude that the process of the fuel and air transformation in the cylinder is controllable, the system is asymptotically stable, and the process is stochastic with the presence of perturbing parameters influenced by the engine's variable modes of operation. The further research areas have been suggested, and the practical results have been predicted: the creation of optimal (in terms of efficiency) control system with the technical solution in the form of the optimal controller (in relation to fuel consumption).

The article presents the results of the study of the influence of deviations of certain design parameters of bogie from established normative values on a relative offset from the crests of wheel pair in mezhdurelsovom space of railway transport. Such deviations occur in the process of the gradual wear of moving parts in real-world conditions of rolling stock and lead to a change of kinematic parameters of bogie. An analysis of dependence of lateral displacement relative to the wheelset of railway track from the difference between the diameters of the tapered surfaces of wheelset, skating from lack of alignment of wheelsets and difference coefficients rigidity of springs of bogie. The proposed mathematical model allows to not only diagnose technical condition of wagon bogies during their movements on the straight section of railway track, but also forecast the rolling stock maintenance dates the whole on the basis of position measurements of wheel pairs regarding railway track.

In article the reasons of shutdowns of high-speed switches of a direct current are analysed and distribution of the disconnected currents is received. Such numerical characteristics as population mean and a mean square deviation of function of distribution of the currents which are disconnected by the high-speed switch are considered. The hypothesis of distribution of probability of refusal in operation of the switch is checked. Conclusions are drawn on applicability of the given calculation methods for definition of admissible number of shutdowns of high-speed switches on sites of traction network of a direct current.

The method of determining the durability indicators of wheel pairs of locomotives is considered on the example of diesel locomotives of the 2TE25KM series operated on the Volga railway. For this purpose, the 90% resource of the wheel pairs of the studied series of locomotives was determined, and it was compared with the accepted standard indicator. In addition, a controlled parameter of the wheelset is selected, limiting the reliability of this node. To conduct the study, methods of mathematical statistics and probability theory were used, in particular, the Laplace distribution function, the Student's criterion, as well as the results of calculations of the dependencies of the mean value and the standard deviation of the controlled parameters, the initial values of developments and operating time corresponding to the probability of failure 0.5. In this study, a mathematical model for assessing the durability of wheelsets from the point of view of reliability theory was developed. The evaluation of the durability indicators of the wheelset elements was carried out on the basis of the type of random variable distribution law with its parameters obtained on a computer and adopted according to the Pearson criterion. As a result of the calculations, 90% of the life of the wheelset was obtained according to two controlled parameters, which amounted to 476.6 thousand km for the thickness of the bandage, and 282.6 thousand km for the thickness of the ridge. The results obtained were compared with the values adopted in the Technical Specifications for this series of locomotives (800 thousand km). km), as well as with statistical data on the values of controlled parameters obtained during processing and analysis - 240 thousand km. Due to the fact that in operation the average life of the wheelset is determined by a larger number of controlled parameters, taking into account unscheduled repairs, and in this study - only on the basis of the thickness of the bandage and the ridge, it is not possible to talk about full compliance with the calculated and actual data. According to the results of calculations, the limiting reliability of the wheelset is such a controlled parameter as the thickness of the ridge. For a more accurate assessment of the durability of wheelsets, it should also be taken into account that the intensity of wear of rolling stock equipment is affected by specific operating conditions, in this regard, inter-repair runs should be adjusted taking into account the influence of external factors during operation. In order to fully assess the durability of wheelsets in the future, it is necessary to take into account additional factors, in addition to those that affect the parametric change of random variables, as well as the fact that takes into account the monitoring and analysis of all controlled parameters of this node during the operation of locomotives.

The article is devoted to the development of a methodology for monitoring the alignment and radial runout of the inner cylindrical seating surfaces of locomotive motor-axle bearings. The main reasons for the wear of the working surfaces of the bearings and the consequences of the influence of the clearances in the interfaces of the plain bearings and the axles of the wheelsets on the increase in the intensity of wear of the parts and the deterioration of the dynamic characteristics of the running gear of the locomotive are listed. The paper presents a basic diagram of the basing and control of deviations from alignment and radial runout of the inner cylindrical surfaces of bearings, describes the design and principle of operation of a special control device for measuring these deviations. The purpose of the work is to substantiate the feasibility of monitoring deviations from the shape and location of surfaces during the repair of motor-axial bearings. The paper describes the sequence of steps for measuring the alignment and radial runout of bearings and the interpretation of the measurement results. The features of the design of the control device are considered, the advantages of its use are listed in comparison with the existing analogues of the devices used to control the alignment of the holes of the body parts located on the same axis. At the same time, it was found that the control of alignment and radial runout must be carried out in order to assess the possible degree of misalignment of the traction motor frame and the axle of the wheelset of the locomotive after repair. Thus, the conclusions obtained confirm the need to tighten quality control of the restoration of locomotive motor-axle bearings by introducing into the production process the operations to control the alignment and radial runout of motor-axle necks and motor-axle bearing liners made of lead bronze, tin or lead-tin babbits.

The article solves the problem of optimal selection of rolling stock within groups according to the criterion of minimum sum of squared deviations of the current values of a given metric on the evaluation of their mathematical expectations for group objects. The solution obtained on the basis of methods based on ideas integer programming using Boolean variables and concepts of the relation between objects and between groups of objects.